# Test 4 Description

Basic Information: This test has 10 problems worth 6 points each for a total of 60 possible points.  The test is closed book and closed notes.

Testing Time: The entire class period will be devoted to the test. At the end of the class period, all test work must be completed. Most students who have studied the material can finish this test in under 45 minutes.

Materials Needed:

 Paper ruled notebook or graph paper at least 2 sheets Pencil pens are allowed Calculator TI-83, TI-84 or comparable graphing calculator Ruler for drawing lines and setting up scales

Problem Descriptions:

1 - Find a normal probability as in #17-22 pp.354-55
1- Find cutoff values corresponding to a normal probability as in #25-27 p.355
1- Find a probability involving the Central Limit Theorem as in #21-24 (b & c only) p.389
1- Find and interpret a confidence interval for a population mean as in #31-34 pp.417-18 or #13-18 pp.431-32.
1- Find and interpret a confidence interval for a population proportion as in #19 (c,d), 20(c,d), 21(c), 22(c,d), 23(c,d) pp.442-43

Other factors being constant, decide how the length of a confidence interval changes with the confidence, the sample size, or the standard deviation.

 Confidence Interval Variation Exploration Confidence Interval Variation Problems
1- Find the minimum sample size necessary to estimate a population mean as in #43-46, 47(a,b), 48(a,b) pp.420-21
1- Find the minimum sample size necessary to estimate a population porportion as in #25-28, 29(a,b), 30(a,b) p.443

Other factors being constant, decide how the minimum sample size changes with the confidence, the margin of error, or the standard deviation.

 Sample Size Variation Exploration Sample Size Variation Problems
1 - Decide whether or not data is normally distributed by looking at a normal probability plot as in #3-8 pp.361-62

 Indicates the calculator has a routine which quickly does most of the work for the problem.

WARNING: The test is open book to allow you to look up any formulas you might have forgotten. You must, however, read and practice the problems before the actual test so you know what method to use and where the needed information is given in the problem statement. Students who take more than an hour usually have not read and practiced the problems sufficiently. Students who do not read and practice the problems beforehand will not finish in the allotted 75 minutes.